Why 21? The concept that a person becomes a full adult at age 21 dates back centuries in English common law, the age at which a person could, among other things, vote and become a knight. Since a person was an official adult at age 21, it seemed to make sense that they could drink then, too.
For part of the 20th century, the drinking age was 18, after then-President Franklin Roosevelt approved lowering the minimum age for the military draft from 21 to 18 during World War II. When the Vietnam-era draft rolled around, though, people objected that if 18-year-old men were mature enough to fight, they were old enough to vote. In 1971, the states ratified the Twenty-sixth Amendment, which lowered the voting age to 18. Legislators applied the same logic to drinking, and the states began reducing the drinking age as well.
Critics of the change decried rises in alcohol-related traffic fatalities among 18- to 20-year-old drivers, especially in areas where “blood borders” were created between states that allowed 18-year-olds to drink and those that didn’t. Teenagers from the more restrictive state would drive into one where they could buy booze, drink, and then drive home, which created a perfect storm for traffic fatalities.
Organizations like Mothers Against Drunk Driving (MADD) began agitating for a uniform national drinking age of 21 to help eliminate these blood borders and keep alcohol out of the hands of supposedly less-mature 18-year-olds. As a result, President Reagan signed the National Minimum Drinking Age Act of 1984, which told states to set a minimum drinking age of 21 or lose up to 10 percent of their federal highway funding. Most states complied quickly. However, the law doesn’t actually prohibit drinking; it only outlaws the purchase and public possession by people under 21. Exceptions include possession (and presumably drinking) for religious practices, while in the company of parents, spouses, or guardians who are over 21, medical uses, and during the course of legal employment.
MADD’s “Why 21?” website touts a National Traffic Highway Administration finding that the raised drinking age policy saves around 900 lives a year. Traffic reports show a 62 percent decrease in alcohol fatalities among teen drivers since 1982, and raw numbers show that drunk-driving fatalities have definitely dropped since the early 1980s: Despite an 88 percent increase in the number of miles driven, 2007 saw over 8,000 fewer total alcohol-related traffic fatalities than 1982.
Critics point out, however, that non-alcohol traffic fatalities have also declined relative to the number of miles driven over the same time period, which could be attributed to any number of causes. And drinking and driving for the whole population might be down as the result of increased education on its consequences, harsher penalties, improved enforcement, or increased stigmatization of drunk driving. (YahooNews)